Data sector pulse generating method

Abstract

A method of generating data sector pulse in a magnetic disk drive includes the steps of servo-writing a bit of index pattern information corresponding to each servo sector in an index area of a servo area on the magnetic disk by a predetermined rule, mapping a data sector pulse timing value with respect to a representative frame of each zone in an inside storage by changing the frame number of relevant zone according to the characteristic of each zone, and reading a sector pulse timing value with respect to a predetermined sector of a predetermined track from the inside storage by deciphering the index pattern information read from the track according to the rule and loading the read result in a gate array for generating the data sector pulse.

What is claimed is: 
     
       1. A method of generating a data sector pulse in a magnetic disk drive comprising the steps of: servo-writing a bit of index pattern information corresponding to each servo sector in an index area of a servo area on said magnetic disk by a predetermined rule;   mapping a data sector pulse timing value with respect to a representative frame of each zone in an inside storage by changing the frame number of a relevant zone according to the characteristic of each zone; and   reading as sector pulse timing value with respect to a predetermined sector of a predetermined track from said inside storage by deciphering said index pattern information read from said track according to said rule and loading the read result in a gate array for generating said data sector pulse:   wherein said index bit information is structured such that plural pieces of index bit information make one group and a plurality of said groups are present on one track, and   wherein each said group comprises a key pattern which identifies the plural pieces of index information as a group and a group value which designates a group number of a corresponding group.   
     
     
       2. A method of generating a data sector pulse in a magnetic disk drive as claimed in claim 1, wherein said group value of adjacent servo sectors are sequential. 
     
     
       3. A method of generating a data sector pulse in a magnetic disk drive as claimed in claim 1, wherein 8 pieces of index information make up each group. 
     
     
       4. A method of generating a data sector pulse in a magnetic disk drive as claimed in claim 3, wherein said key pattern comprises 4 pieces of index bit information. 
     
     
       5. A method of generating a data sector pulse in a magnetic disk drive as claimed in claim 3, wherein said group value comprises 4 pieces of index bit information. 
     
     
       6. A method of generating data sector pulse in a magnetic disk drive where a data sector pulse timing value with respect to a representative frame of each zone is mapped in an inside storage by changing the frame number of relevant zone according to the characteristic of each zone, and a magnetic disk where a bit of index pattern information corresponding to each servo sector is recorded in an index area of a servo area by a predetermined rule during servo-writing, said generating method comprising the steps of: storing index pattern information of a predetermined number following a first index pattern information as a first group value when said first index pattern information of a predetermined sequential number is congruous with a preset key pattern by inputting of a plurality of pieces of said index pattern information read from a predetermined track;   storing index pattern information of a predetermined number following a second index pattern information as a second group value when said second index pattern information of a predetermined number following said first group value is congruous with said key pattern after said first storing step;   calculating a sector number by using said second group value when said first and second group values are in sequence;   determining a current sector number by using the sector number calculated in said calculating step when applied index pattern information is congruous with expectative index pattern information after said calculating step; and   confirming a zone number of a current track by using servo information of a servo area and loading the data sector pulse timing value corresponding to the current sector number of said confirmed zone according to said current sector number in a gate array for generating said data sector pulse.   
     
     
       7. A method of generating data sector pulse in a magnetic disk drive as claimed in claim 6, wherein said key pattern, said first group value and said second group value are comprised of 4 pieces of index pattern information. 
     
     
       8. A method of generating data sector pulse in a magnetic disk drive as claimed in claim 6, wherein said data sector pulse timing value is obtained by the following expression: ##EQU4## wherein the timing value with respect to the last servo sector is read when the remainder is zero.